comb(1) comb(1)
NAME
comb - Combines Source Code Control System (SCCS) deltas
SYNOPSIS
comb [-clist] [-os] [-pSID] file ...
The comb command writes to standard output a shell procedure for combining
the specified deltas (SIDs) of an SCCS file and creating a new version of
the file with fewer deltas.
FLAGS
Each flag or group of flags applies independently to each named file.
-clist
Specifies a list of deltas (SIDs) that the shell procedure will
preserve (see get -ilist). The procedure will combine all other del-
tas.
-o Accesses the reconstructed file at the release of the delta to be
created for each get -e generated; otherwise, accesses the recon-
structed file at the most recent ancestor. Using the -o flag may
decrease the size of the reconstructed SCCS file. It may also alter
the shape of the delta tree of the original file.
-pSID
Specifies the SID of the oldest delta for the resulting procedure to
preserve. All older deltas are combined in the reconstructed file.
-s Causes comb to generate a shell procedure that, instead of combining
the deltas, produces a report for each file, which lists the filename,
size (in blocks) after combining, original size (also in blocks), and
percentage change computed by the following formula:
100 * (original - combined) / original
Run comb using this flag before actually combining SCCS deltas in order
to judge how much space will actually be saved by the combining pro-
cess.
DESCRIPTION
By piping the output of comb to a shell, or redirecting the output to a
file and running that file as a shell procedure, you can reduce the size of
your SCCS file. You can first see how much the file will be reduced by run-
ning comb with the -s flag.
If you specify a directory in place of file, comb performs the requested
actions on all SCCS files (that is, those with filenames with the s. pre-
fix). If you specify a - (dash) in place of file, comb reads standard
input and interprets each line as the name of an SCCS file. comb continues
to take input until it reads End-of-File.
If you do not specify any flags, comb preserves only leaf deltas and the
minimal number of ancestors needed to preserve the tree (see the delta com-
mand).
The comb command may rearrange the shape of the tree deltas.
The comb command may not save any space; in fact, it is possible for the
reconstructed file to actually be larger than the original.
EXAMPLES
1. To generate a report on how much space will be saved by combing all
deltas older than SID 1.4 for SCCS file s.test.c, enter:
comb -p1.4 -s s.test.c | sh
2. To actually combine the deltas, enter:
comb -p1.4 s.test.c | sh
FILES
s.COMB$$
comb$$ Temporary files.
RELATED INFORMATION
Commands: admin(1), cdc(1), delta(1), get(1), prs(1), rmdel(1), sact(1),
sccsdiff(1), sccshelp(1), unget(1), val(1), what(1).
Files: sccsfile(4).